Page 317 - Environment: The Science Behind the Stories

California, Arizona, and Baja California, and each year they Some species act as “umbrellas” that
thrill thousands of people lucky enough to sight the huge birds protect habitat and communities
soaring through the skies. Unfortunately, many of these long-
lived birds still die from lead poisoning, and wild populations Scientists know that protecting species does little good if the
will likely not become sustainable until hunters convert from larger systems they rely on are not also sustained. Yet no law or
lead shot to shot made of copper or steel. treaty exists to protect communities or ecosystems. For these
Other reintroduction programs have been more contro- reasons, conservation biologists often use particular species
versial. The successful program to reintroduce gray wolves to as tools to conserve habitats, communities, and ecosystems.
Yellowstone National Park has proven popular with the Amer- Such species are called umbrella species because they serve
ican public but continues to meet stiff resistance from ranch- as a kind of umbrella to protect many other species. Umbrella
ers, who fear the wolves will attack their livestock. In Arizona species often are large animals that roam great distances, as
and New Mexico, a wolf reintroduction program has made many of the Serengeti’s most notable species do. Because such
slow headway, but a number of wolves there have been shot. animals require large areas, meeting their habitat needs helps
One new idea for saving species from extinction is to meet those of thousands of less charismatic animals, plants,
create individuals by cloning them. In this technique, DNA and fungi that might never elicit as much public interest.
(p. 47) from an endangered species is inserted into a cultured Environmental advocacy organizations have found
egg without a nucleus, and the egg is implanted into a female that using large and charismatic vertebrates as spearheads
of a closely related species that acts as a surrogate mother. for biodiversity conservation is an effective strategy. This
Several mammals have been cloned in this way, with mixed approach of promoting particular flagship species is evident
results. Some scientists even talk of recreating extinct species in the longtime symbol of the World Wide Fund for Nature (in
from DNA recovered from preserved body parts. Indeed, in North America, the World Wildlife Fund), the panda. A large
2009 a subspecies of Pyrenean ibex (a type of mountain goat) endangered animal requiring sizeable stands of undisturbed
was cloned from cells taken from the last surviving individual, bamboo forest, the panda’s lovable appearance has made it a
which had died in 2000. The cloned baby ibex died shortly favorite with the public—and an effective vehicle for soliciting
after birth, however. Even if cloning can succeed from a tech- support for conservation efforts that protect far more than just
nical standpoint, such efforts are not an adequate response to the panda.
biodiversity loss. Without ample habitat and protection in the At the same time, many conservation organizations are
wild, having cloned animals in a zoo does little good. moving beyond the single-species approach. The Nature
Conservancy focuses on whole communities and landscapes;
it purchases lands that preserve important habitats and seeks
Forensics can help to protect species to connect them with other preserved lands so that ecological
processes can function across broad regions.
To counter poaching and other illegal harvesting, scientists
have a new tool at their disposal. Forensic science, or forensics,
involves the scientific analysis of evidence to make an identifi- Parks and protected areas help conserve
cation or answer a question relating to a crime or an accident. biodiversity at the ecosystem level
Conservation biologists are now employing forensics to pro-
tect species at risk. By analyzing DNA from organisms or their Our practice of setting aside areas of undeveloped land to
tissues sold at market, researchers can often determine the be preserved in parks and protected areas helps to conserve
species or subspecies of organism—and sometimes its geo- habitats, communities, ecosystems, and landscapes. Cur-
graphic origin. This information can help detect illegal activ- rently we have set aside 13% of the world’s land area in
ity, enhancing the enforcement of laws protecting wildlife. national parks, state parks, provincial parks, wilderness
A prime example is the analysis of whale meat sold in Asian areas, biosphere reserves, and other protected areas. Many
markets (see The Science behind the Story, pp. 318–319). of these lands are managed for recreation, water quality pro-
Another example is the effort to track the geographic tection, or other purposes, rather than for biodiversity, and
origin of tusks of African elephants killed for ivory. Trade in many suffer from illegal logging, poaching, and resource
ivory has been banned under CITES in an effort to stop the extraction because enforcement is lacking. Yet these areas
slaughter of elephants. After customs agents seized 6.5 tons of offer animals and plants a degree of protection from human
tusks in Singapore in 2002, researchers led by Samuel Wasser persecution, and some are large enough to preserve whole
of the University of Washington analyzed DNA from the tusks natural systems that otherwise would be fragmented,
to determine the geographic origin of the elephants that were degraded, or destroyed.
killed. The researchers sought to find out whether the tusks Serengeti National Park and the adjacent Maasai Mara
belonged to savanna elephants killed in Zambia (the origin National Reserve are two of the world’s largest and most
of the shipment), or whether they came from forest elephants famous parks, but Tanzania and Kenya have each set aside
from other locations. The DNA matched known samples from a number of other protected areas. Some of the best known
Zambian elephants, indicating that many more elephants were include (in Kenya) Amboseli National Park, Tsavo National
being killed there than Zambia’s government had realized. In Park, Mount Kenya National Park, Lake Nakuru National Park,
response, the Zambian government replaced its wildlife direc- and Kakamega Forest National Reserve; and (in Tanzania)
tor and began imposing harsher sentences on poachers and Ngorongoro Conservation Area, Mafia Island Marine Park,
316 ivory smugglers. Selous Game Reserve, Kilimanjaro National Park, and Gombe

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